Add a CLI tool for extracting version numbers from the code. Primarily for checking

the versions during release and to update a table in the docs.

cli/getversionstring.php

+<?php
+// This file is part of Stack - http://stack.maths.ed.ac.uk/
+//
+// Stack is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Stack is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Stack.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Script to extract version numbers from the code.
+ * Primarily for generating the version number mapping but also for
+ * sanity checking and other tool integration.
+ *
+ * @package    qtype_stack
+ * @subpackage cli
+ * @copyright  2023 Aalto University
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+define('CLI_SCRIPT', true);
+
+require(__DIR__ . '/../../../../config.php');
+require_once($CFG->libdir.'/clilib.php');
+require_once($CFG->libdir.'/adminlib.php');
+
+// Fake settings object to catch some values.
+class fakesettings {
+	public $maximaversions = [];
+	function add($some) {
+		if ($some->name === 'maximaversion') {
+			$this->maximaversions = $some->choices;
+			unset($this->maximaversions['default']);
+		}
+	}
+}
+$settings = new fakesettings();
+
+require(__DIR__ . '/../settings.php');
+
+// Fake plugin object.
+$plugin = new stdClass();
+require(__DIR__ . '/../version.php');
+
+
+// Get cli options.
+list($options, $unrecognized) = cli_get_params(['help' => false, 'only' => 'row'], ['h' => 'help']);
+
+if ($unrecognized) {
+    $unrecognized = implode("\n  ", $unrecognized);
+    cli_error(get_string('cliunknowoption', 'admin', $unrecognized));
+}
+
+if ($options['help']) {
+    echo "This script extracts version numbers from various sources in the code
+the numbers it provides are as follows:
+ 
+ - 'pluginversion', the version number, the date one, of the plugin from version.php.
+ - 'pluginname', the version number, the human one, of the plugin from version.php.
+ - 'stackmaxima', the version nubmer at the end of stackmaxima.mac.
+ - 'maximas', the supported Maximas from settings.php.
+ - 'requiredmoodle', the minimum Moodle version.
+
+With the additional option --only one can query for only one of these. 
+e.g. '--only=pluginname'. By default outputs all in the order used in that table in
+the docs.
+";
+    exit(0);
+}
+
+// Read things in.
+$matches = [];
+if (!preg_match('~stackmaximaversion:(\d{10})~',
+    file_get_contents($CFG->dirroot . '/question/type/stack/stack/maxima/stackmaxima.mac'), $matches)) {
+        throw new coding_exception('Maxima libraries version number not found in stackmaxima.mac.');
+}
+// Collect values.
+$stackmaxima = $matches[1];
+$pluginversion = $plugin->version;
+$requiredmoodle = $plugin->requires;
+$pluginname = explode(' ', $plugin->release)[0];
+$maximas = implode(',', $settings->maximaversions);
+
+if ($stackmaxima != $pluginversion) {
+    throw new coding_exception('Maxima libraries version number not matching plugin version number.');	
+}
+
+switch($options['only']) {
+	case 'row':
+		echo "$pluginname | $pluginversion | $maximas\n";
+		break;
+	case 'stackmaxima':
+		echo "stackmaxima\n";
+		break;
+	case 'maximas':
+		echo "$maximas\n";
+		break;
+	case 'pluginversion':
+		echo "$pluginversion\n";
+		break;
+	case 'pluginname':
+		echo "$pluginname\n";
+		break;
+	case 'requiredmoodle':
+		echo "$requiredmoodle\n";
+		break;
+}